Novel compositions based on indanthrone blue pigments

ABSTRACT

A composition comprising 
     (a) an indanthrone blue pigment of formula I ##STR1## and (b) a sulfonated indanthrone blue derivative of formula II ##STR2##  wherein X.sup.⊕ is H.sup.⊕ or a group of the formula M n ⊕ /n or N.sup.⊕ (R)(R 1 )(R 2 )(R 3 ), M is a monovalent, divalent or trivalent metal cation, n is 1, 2 or 3, each of R, R 1 , R 2  and R 3  is independently hydrogen, C 1  -C 18  -alkyl, C 5  -C 6  cycloalkyl, phenyl or phenyl which is substituted by C 1  -C 18  alkyl, or R 2  and R 3 , together with the linking nitrogen atom, are a pyrrolidine, imidazoline, piperidine, piperazine or morpholine radical, or R 1 , R 2  and R 3 , together with the linking nitrogen atom, are a pyrrole, pyridine, picoline, pyrazine, quinoline or isoquinoline radical, and m is a value from 0.2 to 3. 
     When used in varnishes, pigment mixtures of this kind are distinguished in particular by increased color strength, improved rheology and high gloss.

The present invention relates to a composition containing an indanthroneblue pigment and a sulfonated indanthrone blue derivative, and to theuse of said composition for colouring high molecular organic material.

Indanthrone blue pigment has long been known. The improvement of thesolvent resistance of indanthrone blue by adding 30% by weight of asulfonated copper phthalocyanine, based on indanthrone blue, has beendescribed in Japanese published patent specification 71-1707.

Surprisingly, it has now been found that the addition of a sulfonatedindanthrone blue derivative to an indanthrone blue pigment affords apigment mixture having increased colour strength and improvedrheological properties.

Accordingly, the present invention relates to a composition comprising

(a) an indanthrone blue pigment of formula I ##STR3## and (b) asulfonated indanthrone blue derivative of formula II ##STR4## whereinX.sup.⊕ is H.sup.⊕ or a group of the formula M^(n)⊕ /n or N.sup.⊕(R)(R₁)(R₂)(R₃), M is a monovalent, divalent or trivalent metal cation,n is 1, 2 or 3, each of R, R₁, R₂ and R₃ independently is hydrogen, C₁-C₁₈ alkyl, C₅ -C₆ cycloalkyl, phenyl or phenyl which is substituted byC₁ -C₁₈ alkyl, or R₂ and R₃, together with the linking nitrogen atom,are a pyrrolidine, imidazolidine, piperidine, piperazine or morpholineradical, or R₁, R₂ and R₃, together with the linking nitrogen atom, area pyrrole, pyridine, picoline, pyrazine, quinoline or isoquinolineradical, and m is a value from 0.2 to 3.

X.sup.⊕ is preferably H.sup.⊕ or, most preferably, a group of theformula M^(n)⊕ /n.

X.sup.⊕ as a group of the formula M^(n)⊕ /n is for example an alkalimetal cation, an alkaline earth metal cation, an aluminium cation or atransition metal cation, for example Na.sup.⊕, K.sup.⊕, Mg²⊕, Ca²⊕,Sr²⊕, Ba²⊕, Mn²⊕, Cu²⊕, Ni²⊕, Cd²⊕, Co³⊕, Al³⊕ and Cr³⊕, but ispreferably an alkali metal cation or an alkaline earth metal cation (n=1or 2) and, most preferably, is Na.sup.⊕ and Ca²⊕.

C₁ -C₁₈ Alkyl is for example methyl, ethyl, n-propyl, isopropyl,n-butyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, hexyl, heptyl,octyl, decyl, dodecyl, tetradecyl, hexadecyl, heptadecyl or octadecyl.

R, R₁, R₂ and R₃ as C₅ -C₆ cycloalkyl may be cyclopentyl or, preferably,cyclohexyl.

R, R₁, R₂ and R₃ as phenyl substituted by C₁ -C₁₈ alkyl is preferablyphenyl which is substituted by C₁₂ -C₁₈ alkyl.

N.sup.⊕ (R)(R₁)(R₂)(R₃) may be: N.sup.⊕ H₄, N.sup.⊕ H₃ CH₃, N.sup.⊕ H₂(CH₃)₂, N.sup.⊕ H₃ C₂ H₅, N.sup.⊕ H₂ (C₂ H₅)₂, N.sup.⊕ H₃ C₃ H₇ -iso,N.sup.⊕ H₃ -cyclohexyl, N.sup.⊕ H₂ -(cyclohexyl)₂, N.sup.⊕ H₂ (CH₃)(C₆H₅), N.sup.⊕ H₃ C₆ H₅, N.sup.⊕ H₃ -p-octadecylphenyl und N.sup.⊕ (CH₃)₄.

Preferably m is 1.

The sulfonated indanthrone blue component (b) can be prepared by methodswhich are known per se, for example by sulfonation with oleum, sulfuricacid, liquid sulfur trioxide, with or without a catalyst such as boricacid (q.v. German patent specification 216 891), and, in a furtheroptional step, by subsequent reaction with the desired metal salt, e.g.an acetate, chloride, nitrate or, sulfate, or with one of the suitableamines. The concentration of sulfonating agent and the reactionconditions depend closely on the number of sulfonic acid groups which itis desired to introduce into the indanthrone blue molecule.

The compositions of this invention can be prepared by mixing theindividual indanthrone blue components (a) and (b) in the desired ratioor by partial sulfonation and subsequent reaction with a metal salt oramine as described above.

The ratios of the components of the novel compositions can freely vary.Preferred ratios are, however, from 0.2 to 10.0% by weight of component(b) to 99.8 to 90% by weight of component (a), most preferably from 2.0to 6.0% by weight of component (b) to 98.0 to 94% by weight of component(a).

The addition of component (b) can be made before or after conditioningof the pigment. By conditioning is meant preparing a finely particulateform of indanthrone blue, for example by precipitation in alkalinemedium (vatting), precipitation in sulfuric acid, dry grinding with orwithout salt, solvent or wet grinding or, preferably, kneading in thepresence of salts.

Depending on the method of conditioning or on the end use, it can beadvantageous to add specific amounts of texture improving agents to thepigment before or after conditioning, besides the addition of sulfonatedindanthrone blue. Suitable texture improving agents are, in particular,fatty acids of not less than 18 carbon atoms, for example stearic orbehenic acid or the amides or metal salts thereof, preferably magnesiumsalts, as well as plasticisers, waxes, resin acids such as abietic acid,colophonium soap, alkyl phenols or aliphatic alcohols such as stearylalcohol or vicinal diols such as dodecane-1,2-diol, and also modifiedcolophonium/maleate resins or fumaric acid/colophonium resins. Thetexture improving agents are preferably added in amounts of 0.1 to 30%by weight, most preferably of 2 to 15% by weight, based on the finalproduct.

The compositions of this invention are suitable for use as pigments forcolouring high molecular organic material.

Examples of high molecular organic materials which may be coloured orpigmented with the compositions of this invention are cellulose ethersand esters such as ethyl cellulose, nitrocellulose, cellulose acetate,cellulose butyrate, natural resins or synthetic resins such aspolymerisation resins or condensation resins, for example aminoplasts,in particular urea/formaldehyde and melamine/formaldehyde resins, alkydresins, phenolic plastics, polycarbonates, polyolefins, polystyrene,polyvinyl chloride, polyamides, polyurethanes, polyesters, rubber,casein, silicone and silicone resins, singly or in mixtures.

The above high molecular compounds may be singly or as mixtures in theform of plastics, melts or of spinning solutions, varnishes, paints orprinting inks. Depending on the end use, it is advantageous to use thepigments as toners or in the form of preparations. The compositions ofthe invention are preferably employed in an amount of 0.1 to 10% byweight, based on the high molecular organic material to be pigmented.

The pigmenting of the high molecular organic compounds with thecompositions of the invention is carried out for example byincorporating such a composition, optionally in the form of amasterbatch, into the substrates using roll mills, mixing or grindingmachines. The pigmented material is then brought into the desired finalform by methods which are known per se, for example calendering,moulding, extruding, coating, spinning, casting or by injectionmoulding. It is often desirable to incorporate plasticisers into thehigh molecular compounds before processing in order to producenon-brittle mouldings or to diminish their brittleness. Suitableplasticisers are for example esters of phosphoric acid, phthalic acid orsebacic acid. The plasticisers may be incorporated before or afterworking the composition into the polymers. To obtain different shades,it is also possible to add fillers or other chromophoric components suchas white, coloured or black pigments, in any amount, to the highmolecular organic compounds, in addition to the composition of thisinvention.

For pigmenting varnishes and printing inks, the high molecular organicmaterials and the compositions of the invention, together with optionaladditives such as fillers, other pigments, siccatives or plasticisers,are finely dispersed or dissolved in a common organic solvent or mixtureof solvents. The procedure may be such that the individual components bythemselves, or also several jointly, are dispersed or dissolved in thesolvent and subsequently all the components are mixed.

The colourations obtained, for example in plastics, filaments, varnishesor prints, have good allround fastness properties such as gooddispersibility, high transparency, good fastness to over-spraying,migration, heat, light, and weathering.

In addition, compared with unsulfonated indanthrone blue, thecompositions of the invention have greater colour strength, improvedrheology, especially in varnishes and printing inks, exhibit fewerseparating phenomena such as floating out when using white pigmentsconcurrently, have a lesser tendency to flocculate and, in finishes,have a higher gloss.

Because of the good rheological properties of the pigment compositionsof this invention, it is possible to prepare varnishes with higherloadings of pigment.

The compositions of this invention are preferably suitable for colouringaqueous and/or solvent-containing varnishes, especially automotivevarnishes.

The invention is illustrated by the following Examples.

EXAMPLE 1

A steel vessel is charged with 1500 g of steel balls of 1.2 cm diameter,150 g of nails, 135 g of aluminium sulfate.16H₂ O, 15 g of crudeindanthrone blue, 0.75 g of indanthrone blue sulfonic acid obtained bythe process described in German patent specification 216 891 (m=1), and3.2 ml of cyclohexanol. The steel vessel is closed and rolled on aroller bed for 72 hours. The grinding stock is separated from the steelballs and nails, added to 500 ml of water containing 2.5 ml ofconcentrated sulfuric acid, and the pigment suspension is stirred for 2hours at 80°-90° C. The pigment is isolated by filtration at 30° C. andthe filter cake is washed free of salt with water, dried at 80° C. undervacuum and pulverised. The blue pigment so obtained gives very strongcolourations of high saturation when incorporated in varnishes.

EXAMPLE 2

10 g of crude indanthrone blue and 0.3 g of indanthrone blue sulfonicacid (m=1) are stirred at room temperature for 2 hours in 60 ml ofconcentrated sulfuric acid. The mixture is added dropwise to ice-waterat a temperature below 4° C. The batch is stirred for another 2 hours at80° C., filtered, and the filter cake is washed until neutral. Thefilter cake is then suspended in 200 ml water and the suspension isheated to 70° C. Then 1.0 g of dodecane-1,2-diol is added, the mixtureis stirred for 30 minutes at 70° C., then cooled to 30° C. and filtered.The filter cake is washed with water and dried at 80° C. The bluepigment so obtained is most suitable for colouring varnishes and givescolourations of high colour strength, excellent gloss and highsaturation with good fastness properties.

EXAMPLE 3

A 500 ml laboratory kneader is charged with 27 g of crude indanthroneblue, 0.7 g of indanthrone blue sulfuric acid (m=1), 3.7 g ofhydrogenated abietic acid, 130 g of NaCl and 44 ml of diacetone alcohol.The mixture is kneaded for 6 hours without cooling, the temperaturerising to 40° C. The concentrate is charged into 2 liters of water andstirred for 3 hours. The pigment is isolated by filtration and thefilter cake is washed free of salt with water, dried at 80° C. andpulverised. The blue pigment so obtained is most suitable forincorporation in plastics and varnishes and gives colourations of highcolour strength and saturation with good fastness properties. Thevarnishes prepared therewith have excellent rheological properties andhave no tendency to flocculate.

EXAMPLE 4

The procedure of Example 3 is repeated, except for using 1.4 g insteadof 0.7 g of indanthrone blue sulfonic acid. The resultant blue pigmenthas comparably good colouristic and even better rheological properties.

EXAMPLE 5

The procedure of Example 3 is repeated, except for using 2.4 g insteadof 0.7 g of indanthrone blue sulfonic acid. The resultant blue pigmenthas comparably good colouristic and even better rheological properties.

EXAMPLE 6

The procedure of Example 3 is repeated, except for using a mixture of120 g of NaCl and 15 g of CaCl₂ instead of 130 g of NaCl. Theindanthrone blue pigment so obtained contains c. 2.7% of the calciumsalt of indanthrone blue sulfonic acid and has comparably good pigmentproperties.

EXAMPLE 7

The procedure of Example 3 is repeated, except for using a mixture of120 g of NaCl and 10 g of aluminium sulfate instead of 130 g of NaCl.The indanthrone blue pigment so obtained contains c. 2.7% of thealuminium salt of indanthrone blue sulfonic acid and has comparably goodpigment properties.

EXAMPLE 8

The procedure of Example 4 is repeated, except for using a mixture of120 g of NaCl and 10 g of SrCl₂ instead of 130 g of NaCl. Theindanthrone blue pigment so obtained contains c. 5.5% of the Sr salt ofindanthrone blue sulfonic acid and has comparably good pigmentproperties.

EXAMPLE 9

The procedure of Example 3 is repeated, except for using a mixture of120 g of NaCl and 10 g of BaCl₂ instead of 130 g of NaCl. Theindanthrone blue pigment so obtained contains c. 5.5% of the barium saltof indanthrone blue sulfonic acid and has comparably good pigmentproperties.

EXAMPLE 10

The procedure of Example 4 is repeated, except for using a mixture of120 g of NaCl and 15 g of MgCl₂ instead of 130 g of NaCl. Theindanthrone blue pigment so obtained contains c. 5.5% of the magnesiumsalt of indanthrone blue sulfonic acid and has comparably good pigmentproperties.

EXAMPLE 11

A 500 ml laboratory kneader is charged with 27.5 g of crude indanthroneblue, 3.7 g of hydrogenated abietic acid, 130 g of NaCl and 44 ml ofdiacetone alcohol. The mixture is kneaded for 6 hours without externalcooling, whereupon the temperature rises to 40° C. The concentrate isthen charged into 2 liters of water and stirred for 3 hours. The pigmentis isolated by filtration, and the filter cake is washed free of saltwith water and resuspended in 300 ml of water. The suspension is heatedto 70° C., then 1.4 g of the sodium salt of indanthrone blue sulfonicacid are added (m=1) and the batch is stirred for 30 minutes at 70° C.The pigment suspension is then cooled to 30° C. and the pigment isisolated by filtration, washed with water, dried at 80° C. andpulverized. The blue pigment so obtained has excellent rheologicalproperties when incorporated in varnishes, high colour strength andsaturation an excellent fastness to weathering. When incorporated inplastics, the pigment has good dispersibility.

EXAMPLE 12

The procedure of Example 11 is repeated, except for omitting theaddition of 3.7 g of hydrogenated abietic acid. The very productive bluepigment so obtained has excellent rheological properties and, whenincorporated in varnishes, has only a slight tendency to flocculate.

EXAMPLE 13

In a 500 ml glass bead mill having a diameter of 8 cm, 13.5 g of crudeindanthrone blue, 1.5 g of finely particulate hydrogenated abietic acid,0.7 g of the sodium salt of indanthrone blue sulfonic acid (m=1), 125 gof water, 400 g of glass beads of 3.5-4.0 mm diameter are stirred for 12hours at 320 rpm, with external cooling. The speed of rotation of themetal paddle stirrer of 5.5 cm diameter is 0.92 m/sec. The pigmentsuspension is separated from the glass beads, which are washed withwater, and then filtered. The pigment is dried at 80° C., affording 13.5g of a blue pigment containing c. 4% of the sodium salt of indanthroneblue sulfonic acid which, when incorporated in varnishes, gives verystrong colourations of high saturation and good fastness properties andwhich are resistant to flocculation.

EXAMPLE 14

The procedure of Example 13 is repeated, except for using a mixture of100 g of water and 25 g of ethylene glycol instead of 125 g of water.The pigment so obtained has comparably good colouristic properties andvery good dispersibility.

EXAMPLE 15

A 500 ml laboratory kneader is charged with 27 g of crude indanthroneblue, 130 g of NaCl and 44 ml of diacetone alcohol. The mixture is thenkneaded for 61/2 hours while cooling externally with water. Theconcentrate is charged into 2 liters of water and stirred for 3 hours.The pigment is isolated by filtration and washed free of salt withwater. The moist filter cake is resuspended in 400 ml of water and tothe suspension are then added 1.4 g of the n-butylammonium salt ofindanthrone blue sulfuric acid (m=1), obtained by reacting indanthroneblue sulfuric acid with n-butylamine (m=1), and 0.6 g of laurylamine.The batch is then heated to 80° C., stirred for 30 minutes at 80° C. andcooled to 20° C. The pigment is isolated by filtration and the filtercake is washed, dried at 80° C. and pulverised. When incorporated invarnishes, the pigment so obtained is very productive, resistant toflocculation, and gives blue colourations of high saturation.

EXAMPLE 16

15 g of leucoindanthrone in the form of a moist filter cake are added toa mixture of 150 g of water, 9 g of 50% sodium hydroxide solution, 1.2 gof hydrogenated abietic acid and 1.2 g of sodium dithionite. Afteraddition of 220 g of glass beads (diameter c. 1 mm), the aqueoussuspension of the leucoindanthrone is stirred with a high-speed impellerat c. 2000 rpm and 25°-30° C. with admission of air. The pigmentsuspension is separated from the glass beads, which are washed with 300ml of water. The combined suspensions are adjusted to pH 5.0 with dilutehydrochloric acid. The pigment is then isolated by filtration, washedwith water and resuspended in 200 ml of water. To the suspension areadded 0.75 g of the sodium salt of indanthrone blue sulfuric acid (m=1)and the batch is heated to 70° C., stirred for 30 minutes at 70° C.,then cooled to 25° C. The pigment is isolated by filtration and thefilter cake is washed with water and dried at 80° C. When incorporatedin varnishes, the powdered pigment gives very strong blue colourationsof excellent fastness properties.

EXAMPLE 17

A mixture of

130 parts of steatite balls (diameter=8 mm)

47.5 parts of a thermosetting acrylic resin varnish consisting of:

41.3 parts of VIACRYL® VC 373 acrylic resin, 60% (ex VIANOVA KunstharzAG),

16.3 parts of MAPRENAL® TTX melamine resin, 55%, (ex HOECHST AG),

32.8 parts of xylene,

4.6 parts of ethyl glycol acetate,

2.0parts of butyl acetate, and

1.0 part of silicone oil A®, 1% in xylene (ex Bayer), and

2.5 parts of the mixture of indanthrone blue pigments obtained inExample 1

is dispersed in a 200 ml glass bottle with twist-off stopper for 72hours on a roller gear bed. The steatite balls are removed and then

8.0 parts of the dispersed masstone mixture,

0.6 part of ALCOA® aluminium paste (60-65% aluminium content, exAluminium Corp. of America),

1.0 part of methyl ethyl ketone and

18.4 parts of the above thermosetting acrylic varnish

are thoroughly mixed and the mixture is sprayed onto aluminium sheetsand subsequently baked for 30 minutes at 130° C., to give very strongblue metal effect finishes of excellent fastness properties.

Comparably good finishes are obtained by adding a pigment of any one ofExamples 2 to 16 instead of the pigment of Example 1.

EXAMPLE 18

A mixture of 130 g of steatite balls having a diameter of 8 mm, 47.5 gof alkyd/melamine stoving varnish consisting of 60 g of Beckosol® 27-320(Reichhold Chemie AG), 60% in xylene, 36 g of Super-Beckamin® 13-501(Reichhold Chemie AG), 50% in a 2:1 mixture of xylene/butanol, 2 g ofxylene and 2 g of ethylene glycol monomethyl ether, and 2.5 g of themixture of indanthrone blue pigments obtained in Example 3 are dispersedin a 20 ml glass flask with twist-off cap for 120 hours on a roller gearbed. After separating the glass balls, 2.4 g of the dispersed full shademixture are mixed with 60 g of titanium dioxide Kronos® RN 59 (KronosTitan GmbH) and a further 24.0 g of the alkyd/melamine stoving varnish.The coloured varnish solution is sprayed onto aluminium sheets andsubsequently stoved for 30 minutes at 130° C. to give very strong bluefinishes of excellent fastness properties.

EXAMPLE 19

A mixture of 1.0 g of the mixture of indanthrone blue pigments obtainedin Example 4, 1.0 g of antioxidant (®IRGANOX 1010, ex Ciba-Geigy AG) and1000 g of high density polyethylene granules (®Vestolen A 60-16, exChem. Werke Huls) is stirred for 15 minutes in a glass flask on a rollergear table. The mixture is then extruded in two passes in a single screwextruder. The granulate so obtained is moulded to plates at 220° C. inan injection moulding machine (Allround Aarburg 200) and thenpost-formed for 5 minutes at 180° C. The mouldings are coloured instrong blue shades of excellent fastness properties.

EXAMPLE 20

0.6 g of the mixture of indanthrone blue pigments obtained in Example 6are mixed with 67 g of polyvinyl chloride, 33 g of dioctyl phthalate, 2g of dibutyltin laurate and 2 g of titanium dioxide and the mixture isprocessed to a thin sheet on a roll mill for 15 minutes at 160° C. ThePVC sheet so obtained is coloured in a very strong blue shade which isfast to migration and light.

EXAMPLE 21

1000 g of polypropylene granules (®DAPLEN PT-55, ex Chemie Linz) and 20g of a 50% pigment preparation consisting of 10 g of the mixture ofindanthrone blue pigments obtained in Example 7 and 10 g of magnesiumbehenate are thoroughly mixed in a mixing drum. The granules so obtainedare melt spun at 260°-285° C. to blue filaments of good lightfastnessand textile fibre properties.

EXAMPLE 22

(A) 8 g of the mixture of indanthrone blue pigments obtained in Example4 and (B) 23 g of titanium dioxide (KRONOS® RN 59, ex KONOS TITAN GmbH)are each thoroughly dispersed separately in a DISPERMAT® disperser (exHediger, Basserdorf) with 1 mm glass beads in a solution consisting of21.5 g of cellulose acetobutyrate (25% in butyl acetate), 1 g ofzirconium octoate 6 (NUODEX®), 12 g of an aromatic solvent (SOLVESSO®150, ex ESSO), 17.5 g of butyl acetate and 13 g of xylene.

After removal of the glass beads, each of the two dispersions is mixedwith 24 g of DYNAPOL® H 700 polyester resin (60%, ex DYNAMIT NOBEL) and3 g of MAPRENAL® MF 650 melamine resin (55%, ex HOECHST AG). Then 12.5 gof the blue pigment varnish suspension are mixed with 45.0 g of thewhite one. The pigment varnish so obtained is sprayed onto aluminiumsheets and then baked at 130° C., to give strong finishes of excellentgloss.

What is claimed is:
 1. A composition comprising(a) an indanthrone bluepigment of formula I ##STR5## and (b) a sulfonated indanthrone bluederivative of formula II ##STR6## wherein X.sup.⊕ is H.sup.⊕ or a groupof the formula M^(n)⊕ /n or N.sup.⊕ (R)(R₁)(R₂)(R₃), M is a monovalent,divalent or trivalent metal cation, n is 1, 2 or 3, each of R, R₁, R₂and R₃ independently is hydrogen, C₁ -C₁₈ alkyl, C₅ -C₆ cycloalkyl,phenyl or phenyl which is substituted by C₁ -C₁₈ alkyl, or R₂ and R₃,together with the linking nitrogen atom, are a pyrrolidine,imidazolidine, piperidine, piperazine or morpholine radical, or R₁, R₂and R₃, together with the linking nitrogen atom, are a pyrrole,pyridine, picoline, pyrazine, quinoline or isoquinoline radical, and mis a value from 0.2 to
 3. 2. A composition according to claim 1, whereinm is 1 in the sulfonated indanthrone blue derivative of formula II.
 3. Acomposition according to claim 1, wherein X.sup.⊕ in the sulfonatedindanthrone blue derivative of formula II is a group of the formulaM^(n)⊕ /n, wherein M^(n)⊕ is an alkali metal cation or an alkaline earthmetal cation and n is 1 or
 2. 4. A composition according to claim 3,wherein M^(n)⊕ is a sodium or calcium cation.
 5. A composition accordingto claim 1, wherein the ratio of component (a) to component (b) is 99.8to 90% by weight to 0.2 to 10.0% by weight.